Modern processors include multiple instances of processor cores that can be turned on or off independently as directed by a Power Management Unit (execution unit). A multi-core processor, for example, is a single computing component with two or more independent actual central processing units (also referred to as “logical processor,” “cores” or “processor cores”), which are the units that read and execute program instructions. The instructions are typically CPU instructions, but multiple cores can run multiple instructions at the same time, increasing overall speed for programs amenable to parallel computing. Manufacturers typically integrate the cores onto an integrated circuit die, or onto multiple dies in a single package. Homogenous multi-core systems include only identical cores, and heterogeneous multi-core systems have cores that are not identical.